skip to main content

DOE PAGESDOE PAGES

Title: 237Np analytical method using 239Np tracers and application to a contaminated nuclear disposal facility

In this study, environmental 237Np analyses are challenged by low 237Np concentrations and lack of an available yield tracer; we report a rapid, inexpensive 237Np analytical approach employing the short lived 239Np (t1/2 = 2.3 days) as a chemical yield tracer followed by 237Np quantification using inductively coupled plasma-mass spectrometry. 239Np tracer is obtained via separation from a 243Am stock solution and standardized using gamma spectrometry immediately prior to sample processing. Rapid digestions using a commercial, 900 W "Walmart" microwave and Parr microwave vessels result in 99.8 ± 0.1% digestion yields, while chromatographic separations enable Np/U separation factors on the order of 10 6 and total Np yields of 95 ± 4% (2σ). Application of this method to legacy soil samples surrounding a radioactive disposal facility (the Subsurface Disposal Area at Idaho National Laboratory) reveal the presence of low level 237Np contamination within 600 m of this site, with maximum 237Np concentrations on the order of 10 3 times greater than nuclear weapons testing fallout levels.
Authors:
 [1] ;  [2] ;  [2] ;  [3] ; ORCiD logo [3]
  1. Idaho National Lab. (INL), Idaho Falls, ID (United States); Washington State Univ., Pullman, WA (United States)
  2. Washington State Univ., Pullman, WA (United States); Pacific Northwest National Lab. (PNNL), Richland, WA (United States)
  3. Idaho National Lab. (INL), Idaho Falls, ID (United States)
Publication Date:
Report Number(s):
INL/JOU-14-31619
Journal ID: ISSN 0265-931X; PII: S0265931X16304933
Grant/Contract Number:
AC07-05ID14517
Type:
Accepted Manuscript
Journal Name:
Journal of Environmental Radioactivity
Additional Journal Information:
Journal Volume: 172; Journal Issue: C; Journal ID: ISSN 0265-931X
Publisher:
Elsevier
Research Org:
Idaho National Lab. (INL), Idaho Falls, ID (United States)
Sponsoring Org:
USDOE
Country of Publication:
United States
Language:
English
Subject:
38 RADIATION CHEMISTRY, RADIOCHEMISTRY, AND NUCLEAR CHEMISTRY; INL; Np-237; Np-239; SDA; subsurface disposal area
OSTI Identifier:
1357190